Field of the Invention
The present invention relates to an organic light-emitting display device.
Description of Related Art
Organic light-emitting display devices that are recently in the spotlight as next generation display devices have advantages, such as relatively fast response speeds, high light emitting efficiency and luminance and wide viewing angles, since they use organic light-emitting diodes (OLEDs) that emit light by themselves.
Organic light-emitting display devices have a matrix structure in which pixels including organic light-emitting diodes are arranged, in which the brightness of each pixel selected by a scanning signal is controlled according to the grayscale of data.
Each pixel in such an organic light-emitting display device includes an organic light-emitting diode (OLED) as well as a driving transistor for driving the OLED. The driving transistor has unique characteristics such as a threshold voltage and mobility. A difference in the characteristic value between the driving transistors of adjacent pixels may reduce the luminance quality of the corresponding pixels.
Therefore, the development of pixel structures for compensating for the threshold voltage and mobility of the driving transistor is underway.
However, in spite of such compensation technology, information about the threshold voltage is lost by a parasitic capacitor component at the gate node of the driving transistor, which is problematic. The loss in the information about the threshold voltage may lead to a severe non-uniform image quality.